The following is a tabulation of some prior art that presently appears relevant: Pat. No. 6,028,255, issue date 2000 Feb. 22, Patentee Myronyk
A conventional stringed musical instrument typically has an adjustable tuning device which consists of a post and a geared or other leverage system to rotate the post. This invention relates to the typical open ended type of tuning post. A string is attached to the tuning post, and wound around the tuning post to adjust the tension in the string in order to achieve the desired musical pitch or note. The tension in the strings keeps them tightly wound around the tuning posts.
When installing a new string onto the instrument, the initially straight string must be inserted in a small hole or slot perpendicular to the axis of the post, and wound around the post several times before string tension increases. The windings help prevent string slippage when tension increases. There are tuning posts that lock the end of the string to the post prior to winding the post to increase tension, but they still require multiple winds to prevent string breakage where it is locked into place. In practice, the tuning post must be wound with one hand while simultaneously holding the string down and tight to the tuning post with the other hand. The natural tendency of the string is to unwrap itself by flipping over the top of the running post.
When the tension in the strings is released, such as de-tuning for travel or with a collapsible type of instrument, the strings relax to their permanently deformed diameter that is always larger than the diameter of the tuning post. Thus there is always some spring back of the coiled string as its tension is released resulting in the string unwrapping and flipping over the open end of the tuning post.
Therefore, it is advantageous to have a device that keeps the string tight to the post and from unwrapping and flipping over the open end of the tuning post. It is a further advantage if the device allows for normal string tuning without additional manipulation of the device.
U.S. Pat. No. 6,028,255 to Myronyk proposes a metal arm that clamps the strings to a rubber pad attached to the neck. This device is intended to retain the strings tension on the tuning posts by not allowing them slide through the retainer device. This device requires that it be loosened prior to tuning the strings.